Mr Johnson was unable to confirm whether the unidentified man who was later found dead had evaded being spotted during the search, or had stowed away on the insecure trailer at a later point.

The unidentified man was carrying Hepatitis B, and had no tattoos or surgical scars. DNA samples taken from him have so far failed to confirm his identity.

Mr Johnson told the inquest: "The lorry driver started that he arrived at Calais and on the approach road he heard a number of individuals he believed had entered the soft-sided trailer.

"Upon arriving at the port, he notified the authorities."

After the unidentified man's body was found in the UK, two sim cards not registered to anyone traceable were found stitched into his clothing, as well as around 550 euro, Mr Johnson added.

Also found in the lorry trailer were large plastic pipes with urine inside them, indicating someone had been inside for some time. No identity documents were found.

Mr Johnson was unable to confirm whether the unidentified man who was later found dead had evaded being spotted during the search, or had stowed away on the insecure trailer at a later point (file photo)

Asked by assistant coroner Christopher Morris when the man had entered the trailer, Mr Johnson said: "I would say it's impossible to tell because the vehicle was left insecure (following the search).

"There is a hypothesis that he was there when the others were, or he could have entered in the port area."

He added there was no-one else involved in the death and no suspicious circumstances, agreeing that it was a "tragic accident".

A post-mortem examination found the man's death was due to "traumatic compressive asphyxia".

Recording a conclusion of accidental death, Mr Morris said: "I'm unable to record a name for the deceased gentleman - a poignant tragedy given he was probably somebody's brother, son and friend."